Chapter 8
Information Systems
Development &
Acquisition
Chapter 8 Objectives
• Understand the process of IS
management
• Understand the system development life
cycle (SDLC)
• Understand alternative approaches to
system development
• Understand in-house system
development
• Understand external acquisition,
outsourcing, and end-user development
The Need for Structured
Systems Development
• Systems analysis and design – the process of
designing, building, and maintaining information systems
– The individual who performs this task is called
Systems analyst
– Organization wants to hire System analyst because
they have both technical and managerial expertise.
The Need for Structured
Systems Development
• Evolution of IS development
– From “art” to a “discipline”: In the early days of computing it
was considered an art that a very few people could master
– Standardized development methods: The techniques used
to build an IS varies greatly from individual to individual. It
was very difficult to integrate and maintain. To address this
problem, info. Sys. professionals decided to use a
disciplined approach of introducing common methods,
techniques, and tools for building information systems
– Software engineering: This evolution led to the use of the
term software engineering to define what system analyst &
programmer do.
The Need for Structured
Systems Development
Options for Obtaining Information Systems
1.
2.
3.
4.
Build your own
Buy a prepackaged system from a software
development company or consulting firm. Example:
Payroll system.
Outsource development to a 3rd party: outside
organization custom build a system to an
organization’s specifications. Good option when an
organization does not have adequate resources or
expertise.
End user development: Individual users and
departments build their own custom systems to
support their individuals. Example MS. Excel.
The Need for Structured
Systems Development
The Need for Structured
Systems Development
System Construction Process
1. Identify a large IT problem to solve
2. Break the large problem into several
smaller, more manageable pieces
3. Translate each “piece” (small problem) into
computer programs
4. Piece together each program into an
overall comprehensive IS that solves the
problem
The Need for Structured
Systems Development
• The Role of Users in the Systems Development
Process
– It is important for all members of the organization to
understand what is meant by system development
and what activities occur.
– Effective partnership: A close and mutually respectful
working relationship between analysts and users is a
key to project success.
Steps in the Systems Development Process
Steps in the Systems
Development Process
Systems Development Life Cycle (SDLC)
- describes the life of an information system from
conception to retirement.
1. System identification, selection, and planning
2. System analysis
3. System design
4. System implementation
5. System maintenance
Steps in the Systems
Development Process
• Phase 1: System Identification, Selection,
and Planning
– Undertake only those projects critical to mission,
goals, and objectives
– Select a development project from all possible
projects that could be performed
– Different evaluation criteria used to rank potential
projects
Steps in the Systems
Development Process
• Phase 1: System Identification, Selection, and
Planning
– Evaluation criteria
• Strategic alignment: The extent to which the project is viewed as
helping the organization achieve its strategic objectives an d longterm goal.
• Potential benefits: The extent to which the project is viewed as
improving profits, customer service, and the duration of the benefits
• Potential costs and resource availability: The number and types of
resources the project requires and their availability
• Project size / duration: The number of individuals and the length of
time needed to complete the project
• Technical difficulty / risks: The level of technical difficulty involved to
complete the project within a given time and resources
Steps in the Systems
Development Process
• Phase 2: System Analysis
– Collecting System Requirements: Requirement collection is
process of gathering and organizing information from users,
managers, business processes, an documents to understand how a
proposed system should work
• System analysts use a variety of techniques to collect system
requirements
–
–
–
–
Interviews: analysts interview people
Questionnaires: analysts design and administer surveys.
Observations: analysts observe workers at selected times
Document analysis: analysts study business documents
• Critical Success Factors (CSF): analysts ask each person to
define her own personal CSFs.
• Joint Application Design (JAD): Special type of a group meeting
where all users and analysts meet at the same time
Steps in the Systems
Development Process
• Phase 2: System Analysis
– Modeling Organizational Data: To construct an
information system, systems analysts must
understand what data the information system needs
in order to accomplish the intended tasks. To do this
they use data modeling tools to collect and describe
data to users.
• Entity Relationship Diagram (ERD)
– Modeling Organizational Processes and Logic
• Data flows
• Processing logic
A sample ERD for students
Steps in the Systems
Development Process
• Phase 3: System Design
–
–
–
–
Designing forms and reports
Designing interfaces and dialogues
Designing databases and files
Designing processing and logic
Steps in the Systems
Development Process
• Phase 4: System Implementation
– Software programming
– Software testing
• Developmental: Programmers test the correctness
of individual modules and the integration of
multiple modules
• Alpha: Software tester tests whether it meets
design specifications
• Beta: Actual system users test the capability of the
system in the user environment with actual data
Steps in the Systems
Development Process
• Phase 4: System Implementation
– System conversion
•
•
•
•
Parallel
Direct
Phased
Pilot
– System documentation, training, and support
• User and reference guides
• Training and tutorials
• Installation procedures and troubleshooting guides
Steps in the Systems
Development Process
•
Phase 5: System Maintenance
–
Maintenance process steps:
1. Obtain maintenance request
2. Transform requests into changes
3. Design changes
4. Implement changes
Steps in the Systems
Development Process
•
Phase 5: System Maintenance
–
Maintenance types:
1. Corrective maintenance
2. Adaptive maintenance
3. Perfective maintenance
4. Preventive maintenance
Other Approaches to Designing
and Building Systems
•
•
•
Prototyping
Rapid Application Development (RAD)
Object-Oriented Analysis & Design (OOA&D)
Prototyping
Need for Alternatives to Building
Systems Yourself
1.
2.
3.
4.
Limited IS staff
IS staff has limited skill set
IS staff is overworked
Problems with performance of IS staff
Common Alternatives to In-house
Systems Development
•
External acquisition
1.
2.
3.
4.
5.
System identification, selection and planning
Systems analysis
Development of a request for proposal (RFP)
Proposal evaluation
Vendor selection
Common Alternatives to In-house
Systems Development
•
Outsourcing – the practice of turning over
responsibility of some to all of an
organization’s information systems
development and operations to an outside
firm
Common Alternatives to In-house
Systems Development
Why Outsource?
•
–
–
–
–
–
–
–
Cost and quality concerns
Problems in IS performance
Supplier pressures
Simplifying, downsizing, and reengineering
Financial factors
Organizational culture
Internal irritants
Common Alternatives to In-house
Systems Development
Managing the IS outsourcing
relationship
•
–
–
–
Strong CIO oversight
Measurement of milestones, costs, and benefits
Customer relationship management
Not all outsourcing relationships are the
same
•
–
–
–
Basic relationship
Preferred relationship
Strategic relationship
Common Alternatives to In-house
Systems Development
End-user development
•
–
–
–
Benefits of end-user development
Encouraging end-user development
End-user development pitfalls